Lockheed Martin's CEV is winged!!

[starfhury]

Have you been in the mockups of the Apollo CSM? Cramming 5 people in there would be akin to torture. The guys who flew Apollo and those other tin cans had gigantic balls of steel. A week in one of those capsules and almost anyone might have gone insane. The shuttle with it's multiple decks is a yacht in comparison. Apollo was a great awesome achieve which will be remembered as long as people continue to keep historic records. But we have advance since Apollo and need to take advantage of the progress in the intervening 40 years since that project started. <div class="Discussion_UserSignature"> </div>

 

[spacefire]

naja did you check the weights and the dimensions of the two vehicles? <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[spacefire]

I have to agree with you. Although 5 people might fit in the CSM (behind, or under the seats, depends how you look at it, two more should be able to squeeze in), it would be a hell of a tight fit for those two! definitely not suited for more than a day or two, even in zero gravity.<br />Also, what do you do with those folks during reentry? they have to be well strapped in, I don't know if they can just sit there and bob around!<br /> <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[najab]

The 5 person CM was strictly for return from LEO to the surface.<br /><br />I believe that most of the Apollo astronauts will tell you that in free fall, with the couches folded out of the way, the Apollo CM wasn't roomy, but it wasn't that cramped either.

 

[gofer]

You can't use the G number as a single metric. What's also imortant weather they are negative or positive (not sure which is better), along which axis in the human body they are applied, and mostly how long they last. Also, popular rollercoasters in amusement parks pull 5Gs, they just last about 3 seconds or so. Kids ride them. A trained astronaut could pull +7 Gs for about 5 seconds, or 12 Gs for a second, I believe. Apollo crew had no ill effects due to deceleration rates. And that's coming from the Moon! Also in a capsule the body is at parallel [edit] doh! perpendicular, at 90 degrees [/edit] to the g-forces and between this and special chairs, suites and liners extreme G-forces can be mitigated (up to 18Gs (!) for milliseconds, I've read)

 

[starfhury]

Najab,<br /><br />I don't mean to harp on the matter, but Apollo was tiny. I'm mean very tiny. Gemini and Mercury even worst. Hell all three can probably fit the space from the nose of an orbiter to the start of the cargo with tons of room to spare. I have some pictures I took while I was at KSC. I'll try to post one later of the capsule. <div class="Discussion_UserSignature"> </div>

 

[scottb50]

That's inmaterial though. <br /><br />A capsule would be the simplest and easiest means of returning personnel needed to build infrastructure in LEO. Once we start talking commercial passengers then a capsule has less relevence. <br /><br />The point should be developing the market, then expanding it, we don't need passenger capability initially, until we have facilities in place that can handle passengers. The ground work is different, use the pickup trucks and semis to build the facilities, the rest will follow.<br /><br />Personally, I think, it is ridiculous to take a CEV to the Moon or Mars. Why complicate things? The ascent vehicle and the landing vehicle don't have to be the same vehicle. A simple Module could put 20-30 people into LEO but maybe we only need a vehicle that can return five or seven people, it's apples and oranges, most of what goes up will stay there for a long time or indefinitely, when we talk about structural components, anyway.<br /><br /> The primary requirement is going to be putting people and cargo into LEO, not returning people or cargo. <br /><br />What is needed is very specialized vehicles that are optimized for what they do. A First Stage that can take any number of upper stages, an upper stage that can handle any number of payloads and various Modules that can be interchanged to operate in LEO and beyond. <div class="Discussion_UserSignature"> </div>

 

[gofer]

I agree (as a potential customer to go into space), in general, cramped=bad. However:<br /><br />1. the descent lasts a short time<br />2. the Earth descent portion is one of the, heck, THE MOST intense (the plasma at re-entry is over 4500 degrees Centigrate, is that hot or what?!) and critical portion of the flight<br />3. Thus it has to be THE MOST ROBUST AND RUGGED <br />4. NASA doesn't have unlimited funds<br />_________________________<br />Summarry: NO NEED to sink limited funds into developing a better bycicle when what you are after is winning a Formula-1 track; there are plenty of other things that need the investment: (interplanetary propulsion, long term life-support, in-situ development, mining, science, etc...)<br /><br />NASA should be at the *forefront* of *space exploration* *boldly going* and all... It doesnt' need to compound its difficulties re-inventing the 40 years old wheel of returning people to Earth in one piece. If private enterprise creates a viable RLV solution for LEO, MORE POWER TO THEM, I'm rooting for them actually. But NASA... they need to be ALREADY ON THE MOON, by the time the private enterprises are ready to take over the LEO deliveries with whatever...<br /><br />Sorry for a bit emotional posting, nothing personal is meant, I really root for space exploration going forward.

 

[drwayne]

There is a time profile of the g loading in the paper I linked.<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[mrmorris]

<font color="yellow">"... but Apollo was tiny. I'm mean very tiny..."</font><br /><br />And you apparently missed the post where I showed how shifting from a 4m base to a 5m base would <b>triple</b> the interior volume of the craft? Advocating using the Apollo CM <b>shape</b> does not equate to advocating the Apollo CM <b>size</b>.

 

[mrmorris]

<font color="yellow">"Nixon cut it because it made sense to cut it. "</font><br /><br />And because he knew that the Apollo program, and any achievements stemming from it would always be associated with Kennedy and Johnson -- both of whom he detested.

 

[mrmorris]

<font color="yellow">"I think capsules are probably a better choice than lifting bodies for returning from LEO. The Soyuz re-entry module has proven just fine for land recovery operations, so no lifting body is necessary. But for Earth re-entry at the higher speeds and limited timing that a mission beyond LEO entails, I think a lifting body is superior to a capsule."</font><br /><br />You're actually backward. when considering relative utility of the orbit lifting bodies make more sense for use in LEO than interplanetary use. <br /><br />- The LB aspects are only useful in re-entry -- so a spaceraft intended primarily for up-down operations will make the most use of the crossrange you get for the mass penalty. Taking that extra mass to the Moon or Mars is silly.<br />- The higher heat loads from interplanetary returns require a more robust heat shield. Since a lifting body must have TPS over a much larger percentage of its surface than a capsule -- this will result in an increase of the mass discrepancy that already exists.<br /><br />Why do you think that the higher re-entry speeds of a Moon/Mars return favor lifting bodies?

 

[mrmorris]

<font color="yellow">"...we are probably going to have to come back to some sort of return vehicle that can actively fly to where it needs to go. .."</font><br /><br />Going back to Griffin's post again -- one of the things ne noted was: <i>"Most of the Apollo landing dispersions would have fitted easily within the boundaries of Dulles Airport. It is not necessary to do better than that."</i> With a modern computer, better gyros and accelerometers and a GPS system, it's certain that a modern capsule *would* do better than that. If a capsule can be steered to within a half-mile or less of its target -- what exactly is the need to have additional in-atmosphere steering. Also -- as I've noted before -- capsules *can* steer just as well as a lifting body *before* the de-orbit burn. Better in fact, because the lower relative mass means they have a higher dv given equivalent propellant. This pre-deorbit steering can allow thim to be nearly as precise in picking a landing spot as a lifting body.<br /><br /><font color="yellow">"Getting the lifting body/ winged CEV to work will likley force the development of a better TPS system..."</font><br /><br />And if that TPS development effort fails, or produces a functional TPS that is horribly expensive to manufacture and/or operate -- it may well make the craft another white-elephant. NASA has a herd of those already.<br /><br /><font color="yellow">"EELV is just not a strong enough foundation to seriously build our space future on. "</font><br /><br />So in addition to building a CEV, and better recycling technology, and ways to utilize in-situ resources, and better radiation shielding, and space/lunar/martian hab modules, and automated cargo modules, and a new lunar lander, and in-space propellant storage, etc. -- You want to use a lifting body because that would mean throwing out the EELVs and developing something completely new?<br /><br />Your hopes are just a bit too big for NASAs budget.

 

[mrmorris]

<font color="yellow">" I would think the most controversial aspect of the Lockheed CEV is the way it combines the equivalent of the command module and the service module into a single vehicle."</font><br /><br />Not the <b>equivalent</b> by any means. The vast majority of the SM was the propellant and engines for lunar orbit insertion and return. If you look at LM's proposal -- there's the big round thing with engines at the rear which is <b>their</b> propulsion module. However, there are some aspects of the SM that are imbedded in LMs crew module -- namely the fuel cells and a robust ECS. The propulsion capabilities, however, look to be designed strictly for orbital maneuvering -- rendezvousing with the propulsion module, maneuvering for a de-orbit burn, etc.<br /><br /><font color="yellow">"... zipping in from the moon permits only one chance at reentry..."</font><br /><br />Wrong. There are a couple of means of getting 'more chances'. One is to skip off the atmosphere to bleed off speed. You can also use a propellant burn to circularize your orbit around Earth. Or a combination of the two.<br /><br /><font color="yellow">"Lockheed's design for maximum crew safety. "</font><br /><br />LockMart says that so it <b>must</b> be right. <br /><br />*edit* -- fixed CM/SM typo.

 

[najab]

><i>The vast majority of the CM was the propellant and engines for lunar orbit insertion and return.</i><p>I'm sure you meant to say CSM, rather than CM.</p>

 

[drwayne]

I believe the Russians were into the skip methodology.<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[gunsandrockets]

"Why do you think that the higher re-entry speeds of a Moon/Mars return favor lifting bodies?"<br /><br /><br /><br />Lower g load, lower peak temperature compared to a capsule.<br /><br />

 

[gunsandrockets]

Post deleted by gunsandrockets

 

[mrmorris]

<font color="yellow">"I believe the Russians were into the skip methodology. "</font><br /><br />Yep. I couldn't remember what mission offhand, so I didn't bother noting it.

 

[drwayne]

gunsand rockets,<br /><br />Please make more liberal use of the "Return" key, your post was not very readable. Here is some information on skip trajectories for Apollo:<br />http://www.astronautix.com/details/ski16333.htm<br /><br />As I mumbled earlier, skip re-entry was used by the Russians successfully:<br /><br />http://en.wikipedia.org/wiki/Skip_reentry<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[gunsandrockets]

--- " I would think the most controversial aspect of the Lockheed CEV is the way it combines the equivalent of the command module and the service module into a single vehicle."<br /><br /> <br /> <br /><br />Not the equivalent by any means. The vast majority of the CM was the propellant and engines for lunar orbit insertion and return. If you look at LM's proposal -- there's the big round thing with engines at the rear which is their propulsion module. However, there are some aspects of the SM that are imbedded in LMs crew module -- namely the fuel cells and a robust ECS. The propulsion capabilities, however, look to be designed strictly for orbital maneuvering -- rendezvousing with the propulsion module, maneuvering for a de-orbit burn, etc.<br /><br /> <br /> <br /><br />"... zipping in from the moon permits only one chance at reentry..."<br /><br /> <br /> <br /><br />Wrong. There are a couple of means of getting 'more chances'. One is to skip off the atmosphere to bleed off speed. You can also use a propellant burn to circularize your orbit around Earth. Or a combination of the two.<br /><br /> <br /> <br /><br />"Lockheed's design for maximum crew safety. " <br /><br /> <br /> <br /><br />LockMart says that so it must be right. --<br /><br />

 

[mrmorris]

<font color="yellow">"Lower g load, lower peak temperature compared to a capsule."</font><br /><br />Both of which assume you perform an immediate re-entry on return. That's not a requirement as I mentioned in a previous post and I <b>suspect</b> is contraindicated on a Mars return. I expect the heating loads on a direct re-entry from a Mars return would be high enough to make that 'a bad idea'.<br /><br />In any event -- the lower 'peak' heating and G loads of a lifting body mean that the heating and the high-Gs last longer than for a capsule. As has been noted -- a lower G-load for a longer period of time may well be more wearing to the astronauts than a higher one for a shorter period. <br /><br />Ablatives can be designed to handle pretty much any peak temperature that might be contemplated. The *problem* with ablatives is their mass, which (obviously) directly corresponds to how much of it is required. While a lifting body has a lower <b>peak temperature</b>, it has a larger <b>overall heating load</b> . This corresponds to a greater thickness of ablative shielding required. Ergo -- having a lower peak temperature doesn't solve any problems or make anything safer, but having a higher total heat load certainly makes the shield heavier.

 

[gunsandrockets]

I always use the preview function but it isn't working! Gah! It's enraging. I even tried to repost using the space bar to add the missing paragraph spacing, and it's still not working! Grrrrrrrhhh!<br /><br /><br /><br />Bah! Okay, I have it fixed now.

 

[drwayne]

I have seen some speculation that the CM heat shield could have been reused several times, it was just not economical to process it.<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[mrmorris]

<font color="yellow">"And sure the Lockheed CEV is not the equivalent of the Apollo CSM, but then I never said it was. I said the Lockheed CEV is the equivalent of a command module combined with a service module, merely meaning that the Lockheed CEV combines into a single structure what is commonly seperated into different modules in most other manned spacecraft."</font><br /><br />So it's not the equivalent of the CSM -- which is the name of the Command Module and the Service Module conbination, but it <b>is</b> the equivalent of the Command Module and a Service Module. Gotcha -- the sky isn't 'Blue'... it's sort of a pale 'Blue'. Thank you for clearing that up.<br /><br /><font color="yellow">"...it is you who is wrong not me. Bouncing off the atmosphere to bleed off speed would only put you into an orbit that at best would intersect with Earth again after several days if not weeks."</font><br /><br />Sorry -- history tends to suggest that I'm correct. I suppose you've never heard of Zond 6. <i>"The 7K-L1 then made the first successful double skip trajectory, dipping into the earth's atmosphere over Antarctica, slowing from 11 km/sec to suborbital velocity, then skipping back out into space before making a final re-entry onto Soviet territory."</i><br /><br /><font color="yellow">"I remind you that the "much more capable" Apollo CSM was not capable of either of the alternate methods you suggest for returning to Earth."</font><br /><br />The Apollo CM <b>could</b> probably have skipped -- they just had no need to.